From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B42FEC433E0 for ; Thu, 6 Aug 2020 16:56:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1517D2311A for ; Thu, 6 Aug 2020 16:56:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="w1o2nrIr" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729783AbgHFQ4A (ORCPT ); Thu, 6 Aug 2020 12:56:00 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:47178 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728860AbgHFQkn (ORCPT ); Thu, 6 Aug 2020 12:40:43 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 076DIxiX008274; Thu, 6 Aug 2020 13:29:44 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : in-reply-to : references : date : message-id : mime-version : content-type; s=corp-2020-01-29; bh=0cdeMqErhFa6q6fDiKHnaLTgfp6odn/HO4EcR6i6//E=; b=w1o2nrIrqNlbM23C0O6v/5acfayxFWey7Y+Bp761Ts9gBlfht3qWdAh3EXRJ+OIPrpk8 DGa3R0ld6pZZdENBYAsvr7GBDkYyDJTAMB8+hyn/LmLbAiGckHRxQ8kXorIJSi2NBSU7 bB5COLo3N+Ie826mHSMKeIJr5Y1ATm9z1Jd24eCGNCZl2E3+/5ts/ndhy4KLDmanarFQ zrHrXc/FLxK/7jc+1SKE91zJduX9qHd+nIrwOKHIZX+yozUEGr3KtbeCwm31hxVu2gug 5gN1OJmDePWYurP9s2oNDj4jbiwxiJSe7hzZoW2B6B2F2IxDkdPtltebsWlWi3wWay7U eg== Received: from userp3020.oracle.com (userp3020.oracle.com [156.151.31.79]) by aserp2120.oracle.com with ESMTP id 32r6ep2wuk-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Thu, 06 Aug 2020 13:29:44 +0000 Received: from pps.filterd (userp3020.oracle.com [127.0.0.1]) by userp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 076DJMxR031400; Thu, 6 Aug 2020 13:29:43 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by userp3020.oracle.com with ESMTP id 32qy8nch5b-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 06 Aug 2020 13:29:43 +0000 Received: from abhmp0011.oracle.com (abhmp0011.oracle.com [141.146.116.17]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 076DTetC007041; Thu, 6 Aug 2020 13:29:40 GMT Received: from starbug-mbp.localdomain (/79.97.215.145) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 06 Aug 2020 06:29:40 -0700 Received: by starbug-mbp.localdomain (Postfix, from userid 501) id 85D17F04EE7; Thu, 6 Aug 2020 14:29:34 +0100 (IST) From: Darren Kenny To: Jarkko Sakkinen , x86@kernel.org, linux-sgx@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Jarkko Sakkinen , Jethro Beekman , Sean Christopherson , akpm@linux-foundation.org, andriy.shevchenko@linux.intel.com, asapek@google.com, bp@alien8.de, cedric.xing@intel.com, chenalexchen@google.com, conradparker@google.com, cyhanish@google.com, dave.hansen@intel.com, haitao.huang@intel.com, josh@joshtriplett.org, kai.huang@intel.com, kai.svahn@intel.com, kmoy@google.com, ludloff@google.com, luto@kernel.org, nhorman@redhat.com, npmccallum@redhat.com, puiterwijk@redhat.com, rientjes@google.com, tglx@linutronix.de, yaozhangx@google.com Subject: Re: [PATCH v36 09/24] x86/sgx: Add __sgx_alloc_epc_page() and sgx_free_epc_page() In-Reply-To: <20200716135303.276442-10-jarkko.sakkinen@linux.intel.com> References: <20200716135303.276442-1-jarkko.sakkinen@linux.intel.com> <20200716135303.276442-10-jarkko.sakkinen@linux.intel.com> Date: Thu, 06 Aug 2020 14:29:34 +0100 Message-ID: MIME-Version: 1.0 Content-Type: text/plain X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9704 signatures=668679 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=5 malwarescore=0 spamscore=0 bulkscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2008060095 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9704 signatures=668679 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=5 bulkscore=0 malwarescore=0 clxscore=1015 mlxscore=0 priorityscore=1501 adultscore=0 impostorscore=0 lowpriorityscore=0 phishscore=0 spamscore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2008060095 Sender: linux-sgx-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org Archived-At: List-Archive: List-Post: On Thursday, 2020-07-16 at 16:52:48 +03, Jarkko Sakkinen wrote: > Add __sgx_alloc_epc_page(), which iterates through EPC sections and borrows > a page structure that is not used by anyone else. When a page is no longer > needed it must be released with sgx_free_epc_page(). This function > implicitly calls ENCLS[EREMOVE], which will return the page to the > uninitialized state (i.e. not required from caller part). > > Acked-by: Jethro Beekman > Co-developed-by: Sean Christopherson > Signed-off-by: Sean Christopherson > Signed-off-by: Jarkko Sakkinen Reviewed-by: Darren Kenny > --- > arch/x86/kernel/cpu/sgx/main.c | 62 ++++++++++++++++++++++++++++++++++ > arch/x86/kernel/cpu/sgx/sgx.h | 3 ++ > 2 files changed, 65 insertions(+) > > diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c > index c5831e3db14a..97c6895fb6c9 100644 > --- a/arch/x86/kernel/cpu/sgx/main.c > +++ b/arch/x86/kernel/cpu/sgx/main.c > @@ -83,6 +83,68 @@ static bool __init sgx_page_reclaimer_init(void) > return true; > } > > +static struct sgx_epc_page *__sgx_alloc_epc_page_from_section(struct sgx_epc_section *section) > +{ > + struct sgx_epc_page *page; > + > + if (list_empty(§ion->page_list)) > + return NULL; > + > + page = list_first_entry(§ion->page_list, struct sgx_epc_page, list); > + list_del_init(&page->list); > + > + return page; > +} > + > +/** > + * __sgx_alloc_epc_page() - Allocate an EPC page > + * > + * Iterate through EPC sections and borrow a free EPC page to the caller. When a > + * page is no longer needed it must be released with sgx_free_epc_page(). > + * > + * Return: > + * an EPC page, > + * -errno on error > + */ > +struct sgx_epc_page *__sgx_alloc_epc_page(void) > +{ > + struct sgx_epc_section *section; > + struct sgx_epc_page *page; > + int i; > + > + for (i = 0; i < sgx_nr_epc_sections; i++) { > + section = &sgx_epc_sections[i]; > + spin_lock(§ion->lock); > + page = __sgx_alloc_epc_page_from_section(section); > + spin_unlock(§ion->lock); > + > + if (page) > + return page; > + } > + > + return ERR_PTR(-ENOMEM); > +} > + > +/** > + * sgx_free_epc_page() - Free an EPC page > + * @page: an EPC page > + * > + * Call EREMOVE for an EPC page and insert it back to the list of free pages. > + */ > +void sgx_free_epc_page(struct sgx_epc_page *page) > +{ > + struct sgx_epc_section *section = sgx_get_epc_section(page); > + int ret; > + > + ret = __eremove(sgx_get_epc_addr(page)); > + if (WARN_ONCE(ret, "EREMOVE returned %d (0x%x)", ret, ret)) > + return; > + > + spin_lock(§ion->lock); > + list_add_tail(&page->list, §ion->page_list); > + spin_unlock(§ion->lock); > +} > + > static void __init sgx_free_epc_section(struct sgx_epc_section *section) > { > struct sgx_epc_page *page; > diff --git a/arch/x86/kernel/cpu/sgx/sgx.h b/arch/x86/kernel/cpu/sgx/sgx.h > index dff4f5f16d09..fce756c3434b 100644 > --- a/arch/x86/kernel/cpu/sgx/sgx.h > +++ b/arch/x86/kernel/cpu/sgx/sgx.h > @@ -49,4 +49,7 @@ static inline void *sgx_get_epc_addr(struct sgx_epc_page *page) > return section->va + (page->desc & PAGE_MASK) - section->pa; > } > > +struct sgx_epc_page *__sgx_alloc_epc_page(void); > +void sgx_free_epc_page(struct sgx_epc_page *page); > + > #endif /* _X86_SGX_H */ > -- > 2.25.1